/Engine/Source/Runtime/Datasmith/CADKernel/Public/CADKernel/Mesh/MeshEnum.h
3 parametric spaces are defined : -EGridSpaceDefault2Dthe natural parametric space of the carrier surface i.e. for a Bezier surface the boundary of the space is [[0, 1], [0, 1]] and for a spherical surface [[0, 2Pi], [-Pi / 2, Pi / 2]] -EGridSpace::UniformScaled.The average curvilinear length of the iso curves is calculated in each axis.The parametric space is then scaled in each axis such that the average curvilinear length between two points P(A, V) and P(B, V) = B - A.For a spherical surface [[0, 2Pi.R / 2], [-Pi.R / 2, Pi.R / 2]] with R the radius of the sphere -EGridSpace::Scaled.The UnifomeScaled space is rescaled in its most disturbe axis e.g. if V is the most disturbe axis, whatever V, length of[P(A, V), P(B, V)] = (B - A). This parametric space is closed to a good flattening of the surface.
namespace UE { namespace CADKernel { enum EGridSpace { Default2D = 0, Scaled = 1, UniformScaled = 2, EndGridSpace, } } }